The present invention relates to machines for preparing beverages, in particular coffee, by the infusion of a product contained in a capsule or the like.
In the present description and in the appended claims, the term “capsule” means, in general, a package containing a portion of a product, for example, ground roast coffee, suitable for the preparation of a beverage by infusion or percolation.
In this sense, the term “capsule” therefore also means, for example, a so-called filter-paper “pod” or the like.
Previous European patent application EP-1 854 384 A1 describes and illustrates a beverage-preparing machine in which the movement of the capsule-carrying assembly can be controlled by means of an actuator member which is rotatable about an oblique axis parallel to or even coplanar with the plane of movement of the body.
The actuator member has a transverse arm provided with a revolving end roller which is engaged with predetermined clearance in a channel-shaped rolling guide provided in the capsule-carrying assembly. The arrangement is such that, starting from the loading position, a rotation of the actuator member can bring about tilting of the capsule-carrying assembly from a substantially vertical arrangement to an arrangement in which it is inclined and aligned with the hot-water dispensing head. Further rotation of the actuator member can then bring about the translation of the capsule-carrying assembly towards the dispensing head.
To permit both the initial tilting of the capsule-carrying assembly and then its upward translation, the revolving roller of the arm of the actuator member has to be engaged in the associated rolling guide of the capsule-carrying assembly with predetermined clearance. Moreover, to bring about the tilting of the capsule-carrying assembly away from or towards the loading position, the revolving roller has to interact in an oblique direction with one or other of the facing walls or sides of the rolling guide of the capsule-carrying assembly.
In the solution according to EP 1 854 384 A1, the forces that are applied to the revolving roller during the movement of the capsule-carrying assembly are slight whereas they become much greater during the pressing of the capsule-carrying assembly against the dispensing head. This results in a need to over-dimension the bearing associated with the revolving roller.
Moreover, in the solution according to EP 1 854 384, the angle between the working (dispensing) position and the loading position (for the loading of a capsule into the capsule-carrying assembly) is in fact limited: in practice, in the loading position, the capsule-carrying assembly is arranged substantially vertically whereas it would be more convenient for the user if the seat for housing the capsule were directed angularly towards the user.
A further limitation of the solution according to application EP 1 854 384 A1 lies in the fact that the handle for operating the actuator member or rotary shaft has to be gripped and rotated by the user from the front, which is not optimal from the ergonomic point of view.
During the pivoting of the capsule-carrying assembly, the revolving roller also has to interact with the rolling guide in an oblique direction.
In another beverage-preparing machine known from U.S. Pat. No. 4,681,028, a capsule-carrying assembly is mounted so as to be movable between a working position in which it is coupled with the dispensing head and an intermediate position in which the assembly can pivot about an axis towards an angular loading position in which it can receive a capsule.
The kinematic mechanism for actuating the capsule-carrying assembly is not described in detail in this United States patent but seems in any case quite complex.
A further beverage-preparing machine is also known, in which a capsule-carrying assembly is movable between a working position in which it is coupled with the dispensing head and an intermediate position in which the assembly can pivot towards an angular loading position to receive a capsule. In this machine, the kinematic actuating mechanism comprises a rotatable system of levers to which a sliding block is articulated; the sliding block is engaged with a prismatic fit in a corresponding sliding guide of the capsule-carrying assembly. The arrangement is such that the sliding block is permanently engaged in the corresponding guide of the capsule-carrying assembly, even when the assembly is urged towards and against the hot-water dispensing head.